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[en] In spite of the fact that gypsum is one of the most environmentally friendly binders, utilization of gypsum products is relatively narrow. The main problem of gypsum materials is their low resistance to the wet environment and radical decrease of mechanical properties with increasing moisture. The solution of the problem could be in use of composed gypsum-based binders, usually ternary, comprising gypsum, pozzolan and alkali activator of pozzolan reaction. These materials have a better moisture resistance and often also better mechanical properties. Paper provides literature survey of the possible compositions, properties and ways of utilization of the composed gypsum-based binders with latent hydraulic and pozzolan materials together with some results of present research performed by authors. (paper)
[en] The Martian landscape is currently dominated by eolian processes, and eolian dunes are a direct geomorphic expression of the dynamic interaction between the atmosphere and the lithosphere of planets. The timing, frequency, and spatial extent of dune mobility directly reflects changing climatic conditions, therefore, sedimentary depositional ages are important for understanding the paleoclimatic and geomorphologic history of features and processes present on the surface of the Earth or Mars. Optical dating is an established terrestrial dosimetric dating technique that is being developed for this task on Mars. Gypsum and anhydrite are two of the most stable and abundant sulfate species found on the Earth, and they have been discovered in Martian sediments along with various magnesium sulfates and jarosite. In this study, the optical dating properties of various Ca-, Mg-, and Fe-bearing sulfates were documented to help evaluate the influence they may have on in-situ optical dating in eolian environments on Mars. Single-aliquot regenerative-dose (SAR) experimental procedures have been adapted to characterize the radiation dose response and signal stability of the Martian sulfate analogs. Jarosite was dosimetrically inert in our experiments. The radiation dose response of the Ca- and Mg-sulfates was monotonically increasing in all cases with characteristic doses ranging from ∼100 to ∼1000 Gy. Short-term signal fading also varied considerably in the Ca- and Mg-sulfates ranging from ∼0% to ∼40% per decade for these materials. These results suggest that the OSL properties of Ca- and Mg-sulfates will need to be considered when developing protocols for in-situ optical dating on Mars, but more enticingly, our results foreshadow the potential for gypsum to be developed as a geochronometer for Mars or the Earth. - Highlights: → The radiation dose response and OSL signal stability of Ca- and Mg-sulfates was highly variable. → OSL properties of Ca- and Mg-sulfates will need to be considered when developing protocols for in-situ optical dating on Mars. → The results foreshadow the potential for gypsum to be developed as a geochronometer for Mars or the Earth.
[en] The classification and discrimination of minerals are important in geological research. The distribution of rocks and minerals may be inferred based on their identification, which is helpful for the investigation of some geological and environmental evolution problems, either on the earth or on other planets. LIBS and Raman spectra techniques have shown great advantages in simultaneous multi-component, in-situ, and non-destructive detection and they play an important role in rock composition analysis. In this presentation, six kinds of minerals (Gypsum, Spodumene, Barite, Haematite, Moonstone, and Labradorite) were detected by first using LIBS and Raman systems, and then several other methods (PCA, PLS-DA, ANN, and SVM) were used to evaluate the LIBS, Raman, and the fused LIBS/Raman data, respectively. The results indicate the superiority of the fused LIBS/Raman data in mineral classification, which stems from their complementary analysis abilities when studying element composition and structural features. (paper)
[en] The international Phosphogypsum Working Group (PGWG) has its origins in joint meetings of the Stack Free project and the IAEA (2006). These led to formal joint meetings of the IAEA and FIPR (2006, 2007) and to a number of collaborative activities. Out of these activities came two IAEA sponsored meetings on PG, in 2008 and 2009. Another is planned for 2010. The PGWG has adopted the following vision and mission statements. 1. Vision. PG is a resource not a waste. 2. Mission. Find the point of equilibrium between PG production and consumption based on safe, sustainable use. (author)
[en] In this paper, properties of composite materials containing ternary binders are determined. Except gypsum, ternary binders containing also pozzolans and alkaline component, which serve as an activator of pozzolanic reaction. The main aim of this research was to investigate changes in physical and chemical properties and pore structural characteristics due to additions of ternary binders. Experimental results showed that changes in the properties of the composite depend not only on the amount of the addition, but also on the kind of pozzolan. (paper)
[en] The quality of secondary materials is imperative to promote a circular economy. In order to improve the way in which the quality of recycled gypsum is assessed, European guidelines on recycled gypsum (RG) quality criteria have been outlined in the framework of the Life+ Gypsum to Gypsum (GtoG) project. Such GtoG guidelines, along with the European Standard on gypsum plasterboard EN 520, provided the basis for this study. During the GtoG project, gypsum recycling and plasterboard manufacturing processes were monitored by testing the gypsum feedstock and the plasterboard produced. The aim of this paper is to discuss the results obtained on relevant parameters that characterize gypsum as a secondary raw material, as well as the resulting product. The minimum requirements were fulfilled by 56% of the RG samples and 86% of the plasterboard with increased RG.
[es]La calidad de las materias primas secundarias es fundamental para promover una economía circular. En el marco del proyecto Life+ Gypsum to Gypsum (GtoG), y con el objeto de mejorar el análisis de la calidad del yeso reciclado, se han desarrollado orientaciones en cuanto a los criterios de calidad del material. Estas directrices voluntarias, junto a la norma europea EN 520, son la base del presente trabajo. Los procesos de reciclaje y fabricación se monitorizaron durante el proyecto GtoG, mediante el ensayo de materias primas y placas de yeso laminado. El objetivo del presente artículo es discutir las propiedades del yeso como materia prima secundaria, así como del producto obtenido. Un 56% de las muestras de RG y un 86% de las placas con aumento de contenido de RG cumplieron los requisitos mínimos establecidos.
[en] At present, building is considered one of the most polluting activities , however, the sector is becoming aware and taking responsibility for the impact it generates throughout the life cycle of buildings . In the development of the idea of sustainability in the construction, it has been investigated in studies related to the improvement of the conditions of comfort and improvement of the quality of life of the people. In this sense, there are many studies found that intend to incorporate sepiolite for its properties in various materials for the absorption of formaldehydes . Therefore and in view of the results obtained by other authors, the design of a prefabricated panel for indoor false ceiling is proposed. The base material of this panel will be a plaster with sepiolite load in its composition to get it to help improve the indoor air quality of the homes in which it is installed. To achieve the objective, an experimental plan has been developed, divided into three phases: In the first phase, gypsum and plaster were used, following the technical prescriptions of Norma UNE-EN-13279: Yesos de construcción y conglomerantes a base de yeso para la construcción . Said norm, specifies the requirements that this type of material must comply with in terms of hardness, bending and compression, which are the parameters taken into account for this study...
[en] The different systems, and urban subsystems, are not isolated, although today they are managed as such, but integrated into a multidimensional reality where energy flows occur not only within each plane, but between them and in all directions. This integrated reality is an energetic ecosystem, to which we aim to provide balance and sustainability. Once understood this, it is also easy to understand that the mechanisms of rebalancing go through the transfer of the energy resources that are left over in one part of the ecosystem to another part of it where energy is demanded, by the capacity of change of the energy configuration of all the Ecosystem, by the correction of the imbalances and by the symbiotic action between the different systems and subsystems . If we look at the context for opportunities, we see that the two determinants of global development in the coming years are demographic growth and climate change. There is a link between population growth and urbanization in the world in the coming decades, the exponential development of urban areas and the phenomenon of emergence of new megalopolises. The harmonious development of cities is linked to a balance between its density and its complexity . On the other hand, the progressive recovery of urban space for its civic use raises a need to orientate the field of development of the network of infrastructures, services and endowments, towards the underground space. The field of opportunities emerging from integrated management  of underground resources includes the use of subsoil Energy resources for energy capture, exchange and storage. Geothermal exchange allows the inertial use of ground and the built mass buildings and infrastructures, for the accumulation of large quantities of thermal energy with low power and moderate temperature bands, is therefore a Means to accumulate the generated thermal energy and often considered residual, by industrial systems and urban infrastructures and to propitiate its reuse with very low costs, and very long life cycle. The accumulation of thermal energy in the field can also be applied to integrated and distributed systems of solar thermal capture, and solar photovoltaic
[en] The present study describes the lithostratigraphic characteristics of the Canelles Gypsum Formation (lower Keuper) and the Lécera Gypsum Formation (Lower Jurassic) in the area of Camarasa, in the Catalan South Pyrenean front. The Lécera Formation forms a cyclic alternation of gypsum and carbonate layers of about 300 m thick. Gypsum displays gray laminated, white laminated, and white massive lithofacies. Carbonate forms minor layers of dolobreccia and thin bedded dolomicrite lithofacies. On the contrary, the Canelles Formation forms a 100 m thick massive sequence mainly composed of white and brown laminated gypsum, with carbonate layers restricted to the base of the formation and to its middle part. On the base, the carbonate layers consist of laminated dolomicrite lithofacies, while in the middle part they display laminated dolomarl, thin bedded dolomicrite and oolitic lithofacies, which are arranged in four carbonatic cycles of few meters thick. Both formations originated in similar evaporitic environments of very stable sulfate lagoons fed by sea water and away from the influence of detrital inputs. In such lagoons sedimentation mainly consisted of laminated gypsum with minor carbonate beds, representing sediments of relatively high and low concentration of the lagoon water respectively, but without precipitation of more soluble salts (halite).
[es]En el presente estudio se describen las características litoestratigráficas de las formaciones yesíferas de Canelles (Keuper inferior) y de Lécera (Jurásico Inferior) aflorantes en la zona de Camarasa, en el frente Surpirenaico Catalán. La serie de la Fm. Lécera constituye una alternancia cíclica de capas de yesos y carbonatos de cerca de 300 m de espesor. El yeso es de litofacies laminada gris, laminada blanca y masiva blanca. Los carbonatos son brechas dolomíticas y dolomicritas finamente estratificadas. Por el contrario, la Fm. Canelles forma una serie yesífera masiva de 100 m de espesor, con capas menores de carbonato restringidas a la base de la formación y a su parte media. En la base el carbonato es de litofacies dolomicrita laminada, mientras que en la parte media es de litofacies margodolomía laminada, dolomicrita laminada y oolítica, formando cuatro ciclos de pocos metros de espesor. Ambas formaciones se originaron en sistemas evaporíticos de tipo lagoon sulfatado, muy estables, alimentados por aguas marinas y alejados de la influencia de aportes detríticos. En estos lagoons la sedimentación fue principalmente yesífera, en facies laminada, y con niveles subordinados de carbonatados, representando respectivamente estadios de mayor y menor concentración relativa del agua, y sin registro de sales más solubles (halita).
[en] With the development of technology radiation started to be used in variety of different fields. As the radiation is hazardous for human health, it is important to keep radiation dose as low as possible. This is done mainly using shielding materials. Barite is one of the important materials in this purpose. As the barite is not used directly it can be used in some other materials such as fabric. For this purposes barite has been coated on fabric in order to improve radiation shielding properties of fabric. Determination of radiation shielding properties of coated fabric has been done by using computer program written C# language. With this program the images obtained from digital Rontgen films is used to determine radiation shielding properties in terms of image processing numerical values. Those values define radiation shielding and in this way the coated barite effect on radiation shielding properties of fabric has been obtained